Grinding machine



Feb. 19, 1935. L. F. NENNINGER' 1,991,953

A GRINDING MAHINE Filed March '7, 1932 4 Shets-Sheet 1 @www Feb. 19,1935. l.. F. Nr-:NNINGfl-:R .1,991,953

GRINDING y MACHINE Filed Mgroh. '7. 1932 4 Smets-Sheet' 2 nl, VQ

w w H F. NENNINGl-:R A 1,991,953

GRINDING MACHINE Feb. 19,1935.

4 She'etS-Sheet 5 Filed March '7, 1952' Patented Feb. 19, 1935 UNITEDSTATE GRINDING MACHINE Lester F. Nenninger, Cincinnati, Ohio, C cinnatiGrinders Incorporated,

assigner to Cincinnati;

This invention lrelates'to improvements in machine tools and especiallyto improvements in grinding machines.

An object of the invention is the provision of improved means forcontrolling the automatic operation of machine machines, to controlproduced thereby tools, particularly grinding the size ci work piecesbeing and insuring saidwork pieces being held within extremely narrowlimits of size, such as one or two ten-thousandths of an inch.

Another object of the sion of an improved sizing invention is theprovidevice or mechanism that is operated by the work pieces as theypass thereby from the tools of the machine.

Another object of the invention is the provision of a sizing mechanismof the multiplication lever type having the parts means for insuringimproved thereof jointed by the proper positive shift between said partsand in which all side or lateral play is positively eliminated.

Other objects and advantages of the present invention should be readilyapparent by reference to the following specification considered inconjunction with the accompanying drawings, forming a. part thereof, andany modifications may it is to be understood, that be made in the exactstructural details there shown and described within the scope of theappended claims, ing from or exceeding the spirit of without departtheinvention.

in the drawings: Figure 1 is a front elevation of a grinding machineembodying the improvements of this invention.

Figure 2 is a top in Figure 1.

Figure 3 is an ing the grinding throat of a particularly seen from planview of the machine shown elevational view of the parts formcenterlessgrinder as line 3-3 on Figure 1.

Figure 4 is a view partly in elevation and partly in section as seensubstantially from line 4--4 of Figure 3.

Figure 5 is a view partly in elevation and partly in section as seenfrom sectional view taken on line 6-8- Figureiiv is a `of Figure 5.

line 5-5 of Figure 4.

Figure 'I is a fragmentary sectional view on line 7--7 of Figure 3.

Figure 8 is a of Figure 41.

Figure 9 is oi Figure 8.

sectional view taken on line 8-8 sectional view taken on line 9-9 Figure10 is a fragmentary sectional view taken 0n line 10--10 0f Flgureil'isaFigure 8. sectional view through the control face with guideweys ure 9.

Figure 12 is a sectional view compensator taken substantially on ofFigure 9.

Figure 13 is a diagrammatic the electrical circuit involved inThroughout the several views similar reference characters are note thesame or similar parts.

As was noted above, this a'n improved size control s PATENT oFFlcEshowing the piston line 12-12 view illustrating the invention.

of the drawings employed to deinvention pertains to mechanism formachine tools, having particular reference to grinding machines. Theinvention is shown in connection with a centerless grinding machine, butit is to be understood that it is equally applicable to a center typeand other types of grinding machines or any machine tool that removesstock from a work piece, including a feeding mechanism for the tool orwork piece that is to be cut on or increased as the size of the worknears the ultimate desired point.

The grinding machine illustrated in the drawings is of the through feedcenterless type, in which the work pieces are continuously passingthrough the grinding throat is adapted to effect adapted further toother factors when duced to the final desired size.

and which machine a continuous production' and compensatefor wheel wearor the work pieces fail to be re- In general the machine illustrated inthe drawings comprises a bed 15 having rising therefromA at one endthereof a pedestal bearing 16 in which is journaled a spindle 17 for agrinding wheel 18. The spindle and grinding wheel are adapted to berotated at a high grinding rate desirable: means or hi any desirablemanner. The

wheel provides a hood 19 enclosing the grinding of speed by any bracketor shelf 20 supporting a truing mechanism 21 adapted to traverse thegrinding wheel sharp condition.

The bed 15 is further provided 22 for a be adjusted relative thegrinding wheel.

vided with ways 24 for a second the operative face of 18 to maintainsame in a true,

on its upper surslide 23 adapted to to the bed'toward and from The slide23 is further proor upper slide 25 adapted to be actuated relative tothe lower slide 23 or clamped thereto by means of 'a clamp 26 wherebythe said slides are actuated as a unit. In order to eiIect theindependent adjustment of the slides, clamps2'1 are provided forsecuring the lower slide 23`to the bed. integral therewith and risingbracket'or housing '28 to which is The upper slide 25 has therefrom thepivotally secured a head or housing 29 enclosing a spindle 30 carryingat its one end a regulating wheel 31. The regulating wheel and itsspindle are adapted to be rotated at a relatively slow work -rotationcontrolling rate of speed. The grinding wheel 18 and the regulatingWheel 31 are each rotated in a clockwise direction whereby theirproximate portions travel in opposite directions, said portions formingbetween them a grinding throat in which the work is positioned to beoperated upon by the grinding wheel. By oscillating the head or housing29 about the axis of its pivotal connection the regulating wheel iscanted as respects the grinding wheel and Work and thereby effects anaxial feed or travel of the work.

The lower slide.23 is provided at its forward end with a work rest block32 which is positioned beneath the grinding throat and supports a workrest blade 33 peripherally supporting the work 34 as it passes throughthe-said throat. 'I'he block 32 is provided adjacent the vertical sidesof the blade 33 with guides 35 and 36, the former being at the forwardend ofthe throat, while the latter is positioned-at the rear end of thethroat. As shown in Figure 4, and since they are substantiallyduplicates of one another it is presumed a description of one of themwill suffice for the other, the guide 36 comprises opposed guide blocks37 and 38, one positioned on-each side of the blade and each having anangular groove formed in the end side thereof respectively receiving acorrespondingly shaped tongue 39 and 40 formed respectively at the upperend of arms 41 and 42. The said arms are respectively received invertical recesses 43 and 44 formed on opposite sides of the work restblock 32. The arm 41 is pivoted'at 45 'ends of the face.

to the block by the pivot passing through the said recess while the arm42 is similarly pivoted to a rod or shaft 46 extending through therecess 44. 'Ihe block 32 is provided intermediate its upper and lowersurface with a threaded perforation 47 in which is screw threaded a plug48, this plug 48 having a V-shaped notch 49 formed therein to provide acam face 50 adapted to be engaged by the end of an adjusting screw 51.The lower extremity of the arms 41 and 42 terminate in alignment withone another and on opposite ends of an opening or perforation 52 formedthrough theA block 32 near its lower end. A spring 53 extends throughthe perforation 52 and has its opposite ends respectively secured to thesaid lower extremities of the arms 4l and 42 and this spring tends todraw said' extermities to one another, thereby oscillating the arms 41and 42 in opposite directions or tending to separate the guide blocks 37and 38. 'Ihis oscillation of the arms is restrained by the end of theadjusting screw 51 engaging with the cam face 50 and limits theseparation of said blocks, which may be varied by adjusting the screw sothat the end thereof engages the cam face at a point nearer the upper orlower This adjustment is necessary to permit the machine to handle otherthan a single size work piece.

The work pieces on passing from the`grinding throat are supported by ablade 54 which has an inclined operative surface 55 co-operating withthe inclined surface 56 of guide lblock 57 secured to the inclinedportion 58 of a second blade 59 mounted adjacent to the blade 54. Thesaid blades 54 and 59 through the inclined surfaces 55 and 56 form a V-shaped guide trough for guiding the work pieces after they pass from thegrinding throat. The said blades are mounted in a recess 60 formedlongitudinally of a bracket 61 lsecured in any desirable manner, such asby bolts 62 to the rear face of the work rest block 32. The blades 54and 59 are adapted to be vertically adjusted relative to the 'recess 60by means of adjusting screws 63 and 64 to take care of various sizes ofwork pieces and the said. blades are clamped in their adjusted positionsby means of clamp screws 65.

The bracket 6l is formed longitudinally thereof at its upper end with aT-slot 66 receiving the headed end of the bolts 67 which pass throughsuitable perforations formed in a bracket 68. This bracket 68 carriesthe size control mechanism and for this purpose is provided with a slideWay 69 receiving. the tongue '70 of a slide 71. 'I'he slide 71 hasprojecting from it near its upper end a boss 72 in which is rotatablyjournaled the inner end of an adjusting screw 73 threaded in a nut orlug 74 secured to or formed integral with the upper end of the bracketor standard 68. The screw 73 has secured to its outer end a knob 75whereby it may be rotated for adjusting the position of the slide 71 andparts carried thereby. 'I'he slide 71 is held yieldably to its seat bymeans of vsprings 76 which surround studs or bolts 77 extending from thelower surface of the slide 71. The springs abut on one end with the rearface of the bracket or standard 68 and on the other end with lock nuts78 secured thereto. 'I'he slide 71 is provided on its forward surfacewith an elongated boss 79 having formed therein a guide groove 80receiving the tongue 81 projecting from the housing 82. The housing 82is provided with an elongated perforation 83 through which a clamp boltor screw 84 extends having its threaded end received in the lug 79 andwhereby the housing 82 is adjusted laterally of the slide 71. Asl seenin Figures 3 and 5, the housing 82 is substantially L-shaped includingthe hollow vertical arm 85 and the cylindrical arm 86, the formercontaining suitable amplification levers and electrical contacts whilethe latter contains and supports 'the sizing mechanism operating parts.

The cylindrical arm 86 is adapted .to be positioned beyond the grindingthroat so that the Work pieces in passing from the throat passthereunder and if beyond a given size, one ten-thousandth or so of aninch, engagewith feeler finger or feeler member 87. This member 87 isclamped between the fingers of a block 88 which depends below the arm86. 'I'he block 88 is connected by means of flat fulcrum members 89 and90 with a guide block 91 secured in any desirable manner to the swivelhead 92 of the gaging mechanism. The head 92 is integral with or securedto a sleeve 93, which is journaled in a suitable bore formed .in thecylindrical arm 86 of the housing 82. By this construction and as willlater appear, the head 92 may be rotated or oscillated relative to thearm 86 to position the gaging nger or feeler 87 at any desired anglewith respect to the work as it passes thereby. The flat fulcrum members89 and 90 are secured to the guide screws 91 by means of clamp blocks 94and screws 95. Any other desirable method, however, may be used forsecuring these members, such as welding or the like. The upper end ofthe vertically shiftable gage block 88 is connected by the at fulcrum 96to the end of arm 97 of bell crank lever 98. The bell crank lever 98 isconnected by a flat fulcrum member 99 for oscillatory movement to thehead 92 and is adapted to oscillate through the fulcrum member 99 in asingle plane, all other movement being prohibited by the said fulcrum99. 'I'he other arm 100 of the bell crank '98 'is connected by a iiatfulcrum 101 with an axially shiftable rod 102 passing through arelatively large bore 103 in the sleeve 9,3 of the gage head 92. This'rod 102 is formed on the end with a counterbore 104 in which is seated aspring 105 abutting on one end with the base of the counterbore 104 andon the other end with the end of a headed pin 106 slidable within thecounterbore 104. The head 107 of the pin 106 abuts the adjacent end of astop screw 108 adjustably threaded onI the end of a. comparatively longarm 109 positioned within the hollow interior of the arm 85 of L-shapedbracket 82. This arm 109 is pivoted by means of a' flat fulcrum 110which is located near the stop screw or lower end of the arm 109, beingmounted in a boss or lug 111 projecting from the wall of y the arm 85.The 'upper end of the arm 109 is in turn connected by means of a fiatfulcrum 112 with a second vertically disposed arm 113 likewise pivotallymounted by means of a fiat fulcrum 114 to a block or boss 115 carried bythe arm 85 interiorly thereof. The lower end 11S of the arm 113 liesadjacent the end of switch contact member 117, which is adapted to haveits contact 118 placed in engagement with a contact 119 on secondswitchcontact member 120. The switch contactarms 117 and 120 are mounted on aninsulation Ablock 121 which has secured thereto the binding posts 122and 123 for the electrical leads which extend to a compensating device,

feed stop mechanism or the like as will later appear.

'I'he operation of these parts as seen in Figure is as follows. Assumingthe over-sized work piece to be traveling to the left, as seen in Figure5, it will encounter the contact member 87 thereby vertically shiftingthe gage block 88. This is an absolute vertical movement because thefulcrums 89 and 90 will prohibit any side lay. The `vertical shifting ofthe gage block 8 pushes upwardly through the fulcrum 96 against the arm97 of bell crank 98 thereby oscillating it in a clockwise directionabout the fulcrum 99 which again is a iiat fulcrum thereby prohibitingany lateral or sidewise movement and insuring a true arcuate travel ofthe lever. This clockwise oscillation of the lever 98 will through thefulcrum 101 axially shift the rod 102 to the left and again since thefulcrum is aA fiat member prohibiting any lateral or side movementbetween the parts, will urge the rod in a truly axial direction. Theshifting of the rod 102 through the pin 107 which is held in a fixed orstationary position due to the comparatively heavy strength oi thespring 105, will oscillate the arm 109 in a erably nearer' the clockwisedirection about the fulcrum 110. Since this fulcrumlll) is a fiat memberno sidewise movement of the parts can take place, thereby insuring thearm oscillating through a definite plane. Since the fulcrum 110 isplaced considthe upper end of the arm 109 will travel through aconsiderable' distance compared to the travel of the lower end of thearm. This oscillatory movement of the arm 109 will through the fulcrum112 oscillate the short arm 113y in a counterclockwise direction aboutthe fulcrum'l14 and sincel the fulcrums 112 and 114 ar'e again fiatfulcrums,A

no sidewise movement of these arms can takel place insuring the propermovementof the mem-l bers through the desired plane. The oscillatorymovement of the arm 113 will through its end 1 16 force theyieldableswitcharm to the right caus-V `above described for closing lowerorfadjusting screw end,`

I ened and the clamp .27

.due to truing thereof.

through one wall of the arm 85 into contact with the adjacent face ofthe arm 109. The spring 105 above described and contained within thecounterbore v104 likewise exerts a pressure to the right for urging therod102 in that direction and thereby taking the back lash out of all ofthe parts within the gage head 92. lThe adjustable screw 108 on thelower end of the arm 109 will upon actuation of the arm 109 an undueamount engage with adjustablel stop screw 128 carried by one wall of thehollowvarm 85 and will limit the movement of the parts within the arm 85to prevent rupture thereof while the spring 104 would yield, to likewiseprevent rupture of the parts within the gage head 92.

From the foregoing it will be noted that there has been provided amechanism in which every effort has been made to insure the propermovement or actuation of the parts and to eliminate all possible sideplay and thereby out down the ultimate shifting of the parts eliminatinga possible chance of error. Furthermore it will be noted that throughthe large ampliiication in the arm 109 and the further amplification inthe arm113 very slight movement is required of the feeler member 87 andgage block 88 for closing the electrical circuit contact and that saidcontacts may be adjusted to a very line degree for insuring the properoperation of the parts.

As is well known, the work rest blade 33 is provided with an operativeinclined surface 129 which is varied depending upon the size of the workpiece being operated upon and in order that the'proper distance may behad between the operative face 129, of the blade and the knife edgecontact of the feeler 87, the head which carries these parts is,`asabove noted, adjustable through the sleeve 93 for aligning said knifeedge contact of the member'il'l in parallelism with the angle top 129 ofthe blade. In this way a true gage is provided through which the workVpiecesmust pass and if they are slightly over-size even though only oneten-thousandth of an inch, the member 87 will be lifted and therebyoperate the parts the electrical circuit. As was noted above, the upperand lower slides 23 and 25 are adapted to be actuated as a unit andrelative to one another. resorted to for set up purposes to establishthe proper relation between the work rest blade 33 and the Voperativeface of the regulating wheel' 31 and to position said parts with respectto the grinding wheel and establish Athe desired size of -the grindingthroat therebetween. After the parts have been once set up the clamp 26is tightloosened whereupon the two slides move as a unit, which movementhowor .the reduction in the size of the grinding wheel For this purposethere is provided an adjusting screw 130 having its threads received ina nut 131 rotatably journaled in the rear wall of the bracket' orhousing 28. `The other end of therscrew 130 is rotatably mountedl inaThe latter movement is ever is'oniy necessary to take care/ofwheel wear'I'he hydraulic medium ahead of the piston is dis- "15 and the screw isprovided beyond with a pilot; or hand wheel 133 whereby it may are fedtoward one another to reduce succeed- 1 ing through the swivel bracket137 into the path l 144 so that when the segmental gear 141 reaches thelimit of its movement when rotated in a bracket 132 secured to the rearend of the bed .iusted to operate when the work piece is a tenth thisbracket of a thousandth oversize whereupon the wheels be rotated. Thenut 131 is also adapted to be ing work pieces the said tenth ofathousandth. rotated, for which purpose it has keyed or other- When thepiston 147 reaches the end of its movewise secured to it a worm wheel134meshing with ment, it through a pin 172, see Figure 12, ena worm 135 onone end of a worm shaft 136 rof gages a dog 173 on a slide rod 174slidable through tatably journaled in a swivel bracket 137. Sesuitablebearings 175 formed on the swivel houscured to the extreme outer end ofthe worm ing 137. This movement of the rod 174 opens shaft 136 is a handwheel 137a whereby the shaft the normally closed switch 163 against theyieldmay be manually rotated to make fine adjusting resistance ofaspring 176. The rod 174 is proments of the slides 23and 25 as respectsthe bed vided therein with a pair of notches 177 co-oper- 15. Alsocarried by the worm shaft 136 is a ating with a spring loaded detent 178whereby ratchet 138, see Figures 8 and 9, adapted to be the rod is heldin its operative positions for either engaged by a pawl 139 pivoted at140 to a segclosing the switch 163 or holding same open. mental gear 141loosely joumaled on a sleeve 142' It will be appreciated that the workpiece being carried by the swivel bracket 137. A spring 143 gaged issomewhat remote from the work piece abuts the end of theNpawl 139tending tooscillate actually being operated upon so that the parts theend of the pawl toward the ratchet. Extendcannot be returned too rapidlyto their normal positions because a continuous feed would take placeuntil the sliding gage4 block 88 dropped to its normal position to breakthe contacts 118 and 119 for opening the switch 157. Therefore, theexhaust of the hydraulic medium from ahead of the piston when rotatingthe worm to feed the work toward the grinding wheel is unrestrictedwhile when the parts are being returned totheir normal position theexhaust from the other end of the cylinder is restricted. Therefore,soon as the piston 146 reaches the end of its movement of oscillation ofthe pawl 139 is a throw out screw counterclockwise direction, and asseen in Figure 9, the pawl is disengaged from the ratchet so that theshaft 136 may be rotated manually through thehand wheel 137a.

The gear teeth 145 of the gear lil mesh with a rack 146 secured to orformed integral with a piston 147. I'he piston 147 is contained within acylinder 148 formed integral with the swivel to the left, as seen inFigure 9, the solenoid 152 bracket 137. 'I'he bracket 137 is furtherformed is de-energized through the opening of the switch with a valvechamber 149 containing valve spool 63,

ment of the grinding throat.' 'me choke vain 179 is so adjusted as toinsure that the work piece the time the wheels other side by means of awire 164 with the remaining lead 159 or 160, There is also shown in tiontakes place, if necessary.

this figure diagrammatically a tank or sump 165'/ From the foregoing itwill be noted that an containing an hydraulic medium, preferably 011,.improved sizing mechanism has been provided which is adapted to be drawntherefrom through forautomatically compensating for the sin of a pipe166 by a-pump 167 and discharged under work pies being produced andinsuring memo. pressure into` the conduit 168 which terminates ductionof 9,11 work pieces within the me limit. in the valve casing 149. Thespool valve 150 withof tolerane in the casing connects the pressureconduit 16B what is mined is: with a port or conduit 169 whichterminates at 1 In a machine tool orgization the combb one end of thecylinder 148, for actuating. the nat- Piston therein to the left, asseen in Figure 9. porolo.::nzglumtrzzwnzhtg's neanstlgr actuating thework axially -of itself a o m1, terminating 1n the valve casing 149where it is smntble gggppothatteombmmt of connected with the dischreconduit 171- The the work and adapted to. bemoved if the work a movementof the piston rotates the segmental above the desiredsize means operableby the Seal' 141 which thmugh the ratchet and pawl ro' 'axial shiftingof the member for effecting a reltates the worm shaft 136 for rotatingthe worm charged from the cylinder through a conduit 170 adapted toperipherally support the work, and means supporting the axiallyshiftpieces as they pass 35 supported vby said able member foradjustment to disposesame in a plane parallel with the supportingsurface of the work support. l

2. In a centerless grinder the combination of 5 a bed, a pair of opposedgrinding and regulating wheels mounted thereon and forming a grindingthroat therebetween, a work rest blade subtending the grinding throat, atrough disposed be; yond the grinding throat for receiving worktherefrom, feeding means for shifting one of the wheels toward the otherfor varying the size of the grinding throat, an L- shaped bracketsupported above the blade and trough and having one arm thereofcylindrical for bearing purposes, an axially shifted member supported bysaid bearing for contact with and adapted to be axiallyvadjusted by thework when the said work is above the desired size, the other arm of thebracket being of hollow rectangular cross section, control means in saidhollow arm for energizing the feeding means upon actuation of theaxiallyshiftable member.

3. In a centerless grinder the combination of a bed, a pair of opposedgrinding and regulating wheels mounted thereon and forming a grindingthroat therebetween, a work rest blade subtending the grinding throat, atrough disposed beyond the grinding throat for receiving work pieces asthey pass therefrom, feeding means for I shifting one of the wheelstoward the other for varying the size of the grinding throat, an L-shaped bracket supported above the blade and trough and having one armthereof cylindrical for bearing purposes, an axially shifted memberbearing for contact with and adapted to be axially adjusted by the workwhen the said work is above the desired size, the other arm of thebracket being of hollow rectangularcross section, control means i n saidhollow arm for energizing the feeding means upon actuation `of theaxially shiftable member, said control means including a plurality ofmultiplication levers adapted to complete an electrical circuit, and anelectrical circuit between the control means and feeding means.

4. In a. sizing mechanism for use with grinding machines the combinationwith a bracket, of an oscillatory gaging head mounted in the bracket, anaxially shiftable member carried by the bracket for movement in a trulyaxial direction, means connecting the member with the head for insuringsuch axial movement, a bell crank pivotally mounted on the gaging head,means for connect- 'ing the bell crank with the' member for oscillationin a plane parallel with the plane of movement of the member, a rodextending axially through the gaging head for axial movement uponoscillatory movement of the bell crank, and amplication leversoscillatedby the axial shifting of the rod for completing an electricalcircuit.

5. In a sizing mechanism for use with grinding machines the combinationwith a bracket, of an oscillatory 4gaging head mounted in the bracket,an axially shiftable member carried bythe bracket for movement in atruly axial direction, means connecting the member with the head forinsuring such axial movement, a bell crank pivotally mounted on thegaging head, means for connecting the bell crank with the member foroscillation in a plane parallel with the plane of movement `of themember, a rod extending axially through the gaging head for axialmovement `upon oscillatory movement of the bell crank, am-

plification levers oscillated by the axial shifting of the rod forcompleting an electrical circuit,

tween the amplification levers, and additional yielding means foreliminating back lash between the parts carried by the gage head.

6. In a sizing mechanism for use with grinding machines the combinationwith a bracket, of an oscillatory gaging head mounted in the bracket, anaxially shiftable member carried by the bracket for movement in a trulyaxial direction, means connecting the member with the head for insuringsuch axial movement, a bell crank pivotally mounted on the gaging head,means for connecting the bell crank with the member for oscillation in aplane parallel with the plane of movement v of the member, a rodextending axially through the gaging head for axial movement uponoscillatory movement of the bell crank, amplification levers oscillatedby the axial shifting of the rod for completing an electrical circuit,yieldable means for eliminating back lash between the amplificationlevers, additional yielding means for eliminating back lash between theparts carried by the gage head, and means mounting the gage head andparts carried thereby for oscillatory adjustment relative to the bracketfor aligning the member with the work as it passes thereby.

7. In a centerless grinder comprising opposed grinding and regulatingwheels forming a grinding throat therebetween, a work rest bladedisposed in the grinding throat and having an angled operative 'surfaceinclining in the general directionV of the regulating wheel, guidesmounted on opposite sides` of the work rest blade and co-operatingtherewith to form a work receiving trough of a width substantiallyequal-to the diameter of the work, means for adjusting the position ofsaid guides as respects the work rest blade, a bracket exteriorly of thegrinding throat, a gage mechanismcarried by the bracket and including agage head overlying the angled surface of the blade, an axiallyshiftable member carried by the head for contact with the work, andmeans mounting the gage head in the bracket for oscillatory movementrelative thereto to align the operative surface of the axially shiftablemember with the angled top of the blade.

8. In a centerless grinder comprising opposed grinding and regulatingwheels forming a grinding throat therebetween, a work rest bladedisposed in the grinding throat and having an angled operative surfaceinclining in the general direction of the regulating wheel, guidesmounted on opposite sides of the work rest blade and cooperatingtherewith to form a work receiving.

trough of a width substantially equal to the diameter of the work, meansfor adjusting the position i of said guides as respects the work restblade, a bracket exteriorly of the grinding throat, a gage mechanismcarried by the bracket and including a gage head overlying the angledsurface of the blade, an axially shiftable member carried by the headfor contact with the work, means mounting the gage head in the bracketfor oscillatory movement relative thereto to align the operative surfaceof the axially shiftable member with thel mechanism carried by thebracket and including a gage head overlying the angled surface of theblade, an axially shiftable member carried by the head for contact withthe work, means mounting the gage head in the bracket for oscillatorymove- -ment relative thereto to align the operative surface of theaxially shiftable member with the angled top of the blade, means foreffecting a relative feed between the work and grinding wheel, anelectrical circuit including the feeding means for effecting therelative feed between the work and grinding wheel, and means carried bythe bracket operable by the axially shiftable member of the work headfor completing the electrical'circuit, said means comprising contactmembers in the electrical circuit, means adjusting the space betweensaid contacts, and movement amplification levers operable by the axialshifting of the member.

10. In a sizing device for use with machines comprising a bracket, anaxially shiftable member for contact with the work, flat fulcrumsconnecting the member with the bracket whereby the member is suspendedfor movement,

in an axial direction only, a bell crank lever, a flat fulcrumsupporting the bell crank, a fiat fulcrum connecting the axiallyshiftable member with one arm of the bell crank, an axially shiftablerod, a fiat fulcrum connecting the bell crank with the rod whereby axialshifting of the member effects an oscillation of the bell crank andaxial shifting of the rod in a single plane, and means operated by theaxial shifting of the rod for completing an operative electricalcircuit.

11. In a sizing device for use with grinding machines comprising abracket, an axially shiftable member for contact with the work, fiatfulcrums connecting the member with the bracket whereby the member issuspended for movement in an axial direction only, a bell crank lever, anat fulcrum supporting the bell crank, a fiat fulcriim connecting theaxially shiftable member with one arm of the bell crank, an axiallyshiftable rod, a flat fulcrum connecting the bell crank with the rodwhereby axial shifting of the member effects an oscillation of the bellcrank and axial shifting of the rod in a single plane, and meansoperated by the axial shifting of the rod for completing an operativeelectrical circuit, said means comprising oscillatory amplificationlevers, fiat fulcrums connecting said levers to the bracket, flatfulcrums connecting said levers to one another, and electrical contactsadapted to be closed upon movement of said levers.

12. In a sizing device for use with grinding machines comprising abracket, an axially shiftable member for contact with the work, flatfulcrums connecting the member with the bracket whereby the member issuspended for movement in an axial direction only, a bell crank lever, aflat fulcrum supporting the bell crank, a at fulcrum connecting theaxially shiftable member with one arm of the bellcrank, an axiallyshiftable rod, a flat fulcrum connecting the bell crank with the rodwhereby laxial shifting of the member eifects an oscillation of the bellcrank and axial shifting of the rod in a single plane, means operated bythe axial shifting of the rod for completing an operative electricalcircuit, said means comprising oscillatory amplification levers, fiatfulcrums connecting said levers to the bracket, at fulcrums connectingsaid levers to one another, and electrical contacts adapted to be closedupon movement of said levers, and yieldable means operable to eliminateall back lash between the parts.

13. In a sizing device for use with grinding machines comprising abracket, an axially shiftable member for contact with the work, fiatfulcrums connecting the member with the bracket whereby the member issuspended for movement in an axial direction only, a bell crank lever, afiat fulcrum supporting the bell crank, a flat fulcrum connecting theaxiallyA shiftable member with one arm of the bell crank, an axiallyshiftable rod, a flat fulcrum connecting the bell crank with the rodwhereby axial shifting oi' the member effects an oscillation of the bellcrank and axial -shifting of the rod in a single plane, means operatedby the axial shifting of the rod for completing an operative electricalcircuit; said means comprising oscillatory amplification levers, flatfulcrums connecting said levers to the bracket, at fulcrums connectingsaid'levers to one another, and electrical contacts adapted to be closedupon movement of said levers, yieldable means operable to eliminate allback lashbetween the parts, and means mounting the axially shiftablemember and parts operated thereby for adjustment of the parts relativeto the bracket for aligning same with the work to pass thereunder.

14. In a mechanism of the class described the combination with a bed, atool on the bed, a work support adjacent the tool, and means foreffecting a feed between 'the tool and work, of a sizing device forcontrolling the feed means, said sizing device including a contactmember disposed adjacent the work support for engagement with the workas it passes from the tool when the said work is above the desired size,amplification levers associated with the sizing device, flat fulcrumsconnecting.l the levers with one another whereby they are constrained tomove in a given direction, a housing containing the contact member andamplification levers, a bracket supporting the housing, and meansadjusting the position of the housing relative to the bracket towar andfrom the work support.

15. In a mechanism of the class described the combination with a bed', atool on the bed, awork support adjacent the tool, and means foreffecting a feed between the tool and work, of a sizing device forcontrolling the feed means, said sizing device including a contactmember disposed adjacent the work support for engagement with the workas it passes from the tool wher. the said work is above the desiredsize, amplification levers associated with the sizing device, and atfulcrums connecting the levers with one another whereby they areconstrained to'move in a given direction, said contact member beingmounted for adjustment to align same in parallelism with the worksupport. v

16. The combination with a machine tool organization including a tool, awork support adjacent the tool, and means for eifecting a relative feedbetween the work support and tool, of a sizing mechanism overlying thework support for engagement with the work as it passes from the machinecomprising a contact member, a housing supporting the contact member,ampliiication levers within said housing, flat fulcrums connecting saidcontact and amplication levers with the housing and with one another formovement in denite planes, and means further supporting the contactmember for adjustment-relative to the housing to permit same to bedisposed parallel with the work support.

17. The combination with a machine tool organization including a tool, awork support adjacent the tool, and means for eiecting a relative feedbetween the work support and tool, o! a sizing mechanism overlying thework support for engagement with the work as it passes from the machinecomprising a'. contact member, a housing supporting the contact member,amplication'levers within said housing flat fulcrums connecting saidcontact and amplification levers with the housing and with one anotherfor movement in definite planes, means further supporting the contactmember for adjustment relative to the housing to permit same to bedisposed parallel with the work support, hydro-electric means foractuating the feeding mechanism, and electrical contacts operable by theamplcation levers for energizing the hydro-electric means and actuatingthe feeding mechanism.

